Component of a laser treatment device and laser treatment device with a lighting system

ABSTRACT

Laser treatment appliance having an illumination system, in particular for use in the field of medicine, has a laser light source for producing a treatment laser beam which is guided essentially freely, as well as an illuminating light source for producing a visible light for illuminating an area to be treated, and one or more first optical elements via which the treatment laser beam is passed on, with at least one of the first optical elements being in the form of an optical multifunction element, such that the visible light for illumination is also steered at least over this at least one optical multifunction element. The laser treatment appliance furthermore has an optical evaluation apparatus for diagnosis or analysis of radiation which is produced during the treatment process, and all the optical multifunction elements are designed such that they influence the treatment laser beam and the visible illuminating light essentially in an equivalent reflecting and/or transmitting manner. The laser treatment appliance furthermore has a beam splitter, which extends at least over the entire cross section of the treatment laser beam, for outputting the radiation, and which is arranged between the laser light source and the first multifunction element in the incidence direction of the treatment laser beam such that the visible light from the illuminating light source does not pass through it.

[0001] The present invention relates to a component of a laser treatmentappliance having an illumination system, in particular for use in thefield of medicine, with the laser treatment appliance having a laserlight source for producing a treatment laser beam, and an illuminatinglight source for producing visible light for illuminating an area to betreated, and with the component having one or more first opticalelements, via which the treatment laser beam is passed on. The inventionfurthermore relates to a laser treatment appliance having anillumination system, especially for use in the field of medicine, havinga laser light source and an illuminating light source.

BACKGROUND

[0002] Various treatment appliances are known in particular from thefield of dentistry, in which both treatment appliances having mechanicaltreatment elements, such as a drill, and treatment appliances which usea laser beam instead of the mechanical treatment elements are used.

[0003] Depending on the field of application, it is advantageous ornecessary to illuminate the area to be treated, in order to createsuitable lighting conditions for the operator of the appliances.Particularly in areas where access is difficult, as is the caseespecially in the field of dentistry, it is frequently difficult toilluminate the area to be treated using external illumination sources,in particular because the treatment or processing appliance, and/or theoperator himself, shadows the area to be treated.

[0004] Appliances are therefore known from the prior art in whichillumination apparatuses which are designed integrally with thetreatment appliance are provided. By way of example, DE 33 32628 C2discloses a dentistry handpiece, which has a treatment head to which amechanical treatment tool is fitted. The handpiece furthermore has anoptical fiber, which is passed through the handpiece and is passed outof the handpiece at the side, close to the treatment tool, so that thetreatment tool as well as the area to be treated can be illuminated bymeans of an illuminating light source.

[0005] DE 3328604 A1 furthermore discloses a tartar removal tool, which,similarly to the appliance disclosed in DE 33 32628 C2, has a treatmenttool in a front region, in this case a tartar removal tool, which iscaused to oscillate. An optical fiber is passed through the handpiece inthe apparatus disclosed in this document as well, with the optical fiberopening in the vicinity of the treatment tool, and being intended toilluminate the area to be treated, by means of an illuminating lightsource.

[0006] The known illumination systems according to the prior art havethe disadvantage that the supply for the optical fiber is relativelycomplex and hence costly, with the optical fiber also being relativelysensitive, which, over the course of the life of a correspondingappliance, can lead to decreases in the illumination light intensitythat is available. Furthermore, if the optical fiber is destroyed, theentire optical fiber must be replaced, which is highly costly or, insome circumstances, is no longer financially possible at all.

[0007] Furthermore, depending on the treatment tool, the illumination ofthe area to be treated is not optimum, as is the case especially withdrills, in which the light is supplied through an optical fiber fittedat the side.

[0008] DE 33 19203 A1 furthermore discloses a method and an apparatusfor dose measurements for photocoagulation, in which monochromatic laserlight coming from a laser, on the one hand, and light from a lamp forobject illumination, on the other hand, are passed via a chromatic beamsplitter onto a sample, with the chromatic beam splitter being permeableto the light from the lamp for object illumination, that is to sayhaving a transmitting effect, while the beam splitter acts as areflector for the laser light. Fluorescent light emerging from thesample is at least partially emitted through a beam splitter, which istransparent for this fluorescence light but is reflective for the lightfrom the lamp for object illumination, so that at least a portion of thefluorescence light can be evaluated using a photomultiplier.

[0009] WO 01/19454 A2 further discloses a laser apparatus in which, inaddition to a laser diode for producing laser light, there is also adiode for producing a so-called “guide light”. The light from the twolight sources is also in this case injected via a monochromatic beamsplitter, with the beam splitter being completely reflective for theso-called guide light.

[0010] These systems according to the prior art have, in particular, thedisadvantage that, in the case where the radiation produced during thetreatment process or the spectroscopic light is in a wavelength band,which corresponds to the wavelength band of the illuminating light, oroverlaps it, diagnosis or analysis is impossible, or is feasible onlywith very great difficulty, especially in the case of weak radiationand/or weak spectroscopic light, since the spectroscopic light cannot beemitted, or can be emitted only inadequately, in the at leastoverlapping wavelength band.

[0011] One object of the present invention is thus to provide a lasertreatment appliance having an illumination system, which avoids theabovementioned disadvantages of the prior art and, in particular,provides an effective illumination system and an effective capabilityfor diagnosis or analysis of the treatment process, in a simple andcost-effective manner.

[0012] This object is achieved by a laser treatment appliance with theparticularly advantageous embodiments of the laser treat applianceaccording to the invention.

SUMMARY OF THE INVENTION

[0013] According to the invention, the laser treatment appliance thushas one or more optical multifunction elements, which are all designedsuch that they essentially have a comparable influence on the treatmentlaser beam on the one hand and on the visible light for illumination onthe other hand, in which case this should be understood as meaning thatthe multifunction elements are either reflective for the wavelengths ofboth the treatment laser beam and of the visible illuminating light, orelse are designed to be transmissive for both wavelengths or wavelengthbands, so that the optical multifunction elements according to thisinvention are not chromatic beam splitters, as were regarded as beingnecessary in the prior art until now, at least for injecting and joiningtogether the treatment laser beam and the illuminating light.

[0014] The configuration of the laser treatment appliance according tothe invention thus firstly makes it possible for the first opticalelements (which are required in any case in order to steer the treatmentlaser beam produced by the laser light source onto the area to betreated) are at least partially likewise used for steering visible lightfrom the illuminating light source onto the area to be treated, whilesecondly allowing radiation which is produced during the treatmentprocess to be supplied in an effective manner to the optical evaluationapparatus, in particular to a spectrometer, with losses being avoided.

[0015] Furthermore, the first optical elements for guiding or steering,directing the treatment laser beam are generally very high-qualityoptical elements, so that the illuminating light can also be passed onvery effectively. For cost reasons, such high quality elements aregenerally not used for illumination, so that the present invention atthe same time results in a double effect, firstly a cost reduction,since optical elements are spared, and secondly a qualitativeimprovement, since very high quality optical elements can also be usedfor the visible illuminating light.

[0016] At this point, it should be noted that the wavelength of thetreatment laser beam is generally not in the visible band. Owing to thedifferent geometric configurations and focussing of the treatment laserbeam in comparison to desired illuminating light, however, the laserbeam is in principle not suitable for illuminating the area to betreated, irrespective of its wavelength, since the treatment laser beammust generally be focussed at a treatment point, while the illuminatinglight is intended to illuminate a larger area around the point to betreated as uniformly as possible.

[0017] The same also applies to any so-called pilot laser beams whichmay be used to emit light in the visible band and are used as an “aimingapparatus” in order to indicate to the operator the point on thematerial to be treated at which the treatment laser beam is acting orwill act, with this treatment laser beam possibly being invisible to theuser.

[0018] Irrespective of the focussing, a pilot laser beam such as thiswould not be suitable for use as illuminating light even if it wereoptically broadened since, in a case such as this, the high coherencelength would lead to destructive interference phenomena on the surfaceof the material to be treated, resulting in the production of so-calledspeckles, which appear as black or dark spots in the illuminated areaand thus prevent undisturbed identification of details, which isactually the aim of the illumination to avoid. The appearance ofspeckles can lead to the identification of details frequently beingconsiderably poorer than without the possibly widened pilot laser beam.The same applies analogously to any laser light source which may bepresent and is used for diagnosis purposes, for example for stimulationof fluorescence.

[0019] For the purposes of the invention, the expression “opticalelements” should be understood as meaning all known optical elements inthe widest sense, not only elements which influence the profile of thelight or of the laser beam, such as steering, focussing, reflectingelements, or elements which influence the incident light in some otherway. Furthermore, for the purposes of the invention the expression“optical elements” also covers elements which do not significantlyinfluence the profile of the light which strikes them or of a treatmentlaser beam, such as outlet apertures or termination plates, which areessentially completely transmissive for the wavelength of thecorresponding light. In addition, no deflection or bending takes placewhen passing through such an optical element (or such deflection isnegligible). Optical elements may, in particular, be mirrors,waveguides, optical fibers, such as glass fibers, covering windows oroutlet windows.

[0020] Furthermore, it shall be mentioned that an optical element mayalso have different areas, with different affects in these areas. Forthe purposes of the invention, an optical element may be, for example, amirror which is designed to be essentially planar over a wide region,but which is curved in an edge area. In principle, it is also possiblefor an optical element to have clear boundaries between the variousareas, such as edges or coatings, and, for example, even non-reflectivecoatings. Furthermore, it is possible for an optical element also to besplit in two, for the purposes of the invention, in order to produce thedesired effects.

[0021] For the purposes of the invention, both a simple laser such as adiode laser and a complex laser apparatus, which may possibly also havea number of individual lasers, should be regarded as a “laser lightsource”, for example having an associated pump laser in addition to thelaser which produces the treatment laser light. For the purposes of theinvention, the laser light source may also have any associatedappliances, such as frequency converters, etc.

[0022] For the purposes of the invention, the expression “illuminatinglight source” should be understood as meaning a light source which doesnot exclusively emit essentially monochromatic light, such as laserlight. An illuminating light source such as this may comprise one ormore in principle undefined light sources, but it is also possible foronly one apparatus to be regarded as an illuminating light source forthe purposes of the invention, which introduces or injects light intothe laser treatment appliance from some other source, which need not bepart of the laser treatment appliance. This also includes, for example,a mirror apparatus which uses daylight or external light forillumination, and which likewise satisfies the desired requirements. Itis preferable for the illuminating light source to emit white light in apreferred manner, preferably at least composed of at least two, andespecially at least three, central wavelengths, whose coherence lengthis chosen appropriately in order to avoid, in particular, theabovementioned speckles, which do not allow effective illumination. Inparticular, an illuminating light is desirable which has a verybroadband frequency or wavelength distribution. In particular,illuminating light sources are preferably used which comply with therequirements of the DIN Standards for workplace illumination, inparticular with DIN Standard 5035 (in particular Part 1) and 6169 (inparticular Parts 1 and 2), whose entire contents are included by directreference in this application.

[0023] In one preferred embodiment, the component according to theinvention is designed such that the treatment laser beam which iscarried in it is guided essentially freely. Free guidance of the laserbeam should be understood as meaning extensive guidance in anessentially free interior of the component, which may be filled with airor a gas, and which may possibly also be at a reduced pressure or maybea vacuum. The guidance of the laser beam in this free interior of thecomponent is steered and aligned or focussed by means of the firstoptical elements mentioned above, in particular, by means of mirrors andlenses as well as windows.

[0024] In one such embodiment, an extremely large number of degrees offreedom are available both for the treatment laser beam and foradditional guidance of the visible light for illumination, likewise inthe interior of the component, and in particular using as many firstoptical elements as possible.

[0025] The component preferably also has a first optical element, whichis essentially in the form of an outlet window which is designed to betransmissive for the laser treatment light and which does notsignificantly influence the profile of the treatment laser beam. Anoutlet window such as this is generally provided for termination of thetreatment end of the component, in particular of the handpiece, in orderto shield the interior from the outside. If the illuminating light islikewise passed through this outlet window. Then this results especiallyin highly effective illumination, since the visible light forillumination is emitted essentially from the same direction andparallel, as well as preferably in the same spatial area as thetreatment laser beam. Thus shadowing is avoided even in areas whereaccess is very difficult, especially in the field of dentistry, withroot treatment being mentioned in particular, here, by way of example.

[0026] In addition to the described embodiment, in which the outletwindow of the component is in the form of an optical multifunctionelement, an embodiment is, of course, also feasible in which, inaddition to the outlet window, an inlet window of such a component mayalso be in the form of an optical multifunction element for passing onor steering both the treatment laser beam and the visible light forillumination.

[0027] However, it is particularly preferable for such first opticalelements to be in the form of optical multifunction elements, which notonly shield a specific spatial area and do not significantly influencethe treatment laser beam and/or the visible light for illumination, butwhich are in the form of elements which influence the treatment laserbeam and/or the visible light for illumination. These include lenseswhich focus, broaden or in some other way influence light passingthrough them, or mirror elements, which steer the laser beam in thedesired direction, especially in the internal area of the component witha laser beam which is guided freely, in which case such mirrors maylikewise have focusing or widening functions. This makes it possibl forthe visible light for illumination to take a path through the componentwhose route is similar, at least in large areas, to the predeterminedroute of the treatment laser beam. No additional elements are requiredfor steering or influencing the visible light.

[0028] The greater the extent to which the first optical elements forthe treatment laser beam are in the form of optical multifunctionelements, the fewer additional optical elements are required, and theseare provided only for the visible light for illumination.

[0029] In a further preferred embodiment of the component according tothe invention, this component has an optical element for injecting theilluminating light into the component. An optical element such as thisis required when the illuminating light source is not provided in thecomponent, with the component thus being a centerpiece or an end pieceat the treatment end, in particular the handpiece, and with theilluminating light source being provided in elements or components whichare further away from the treatment end of the apparatus. This isparticularly advantageous because the end pieces at the treatment end,especially the handpiece, frequently have to be sterilized, at least inmedical fields, In this case it is advantageous for sensitive elementsor elements which are difficult to sterilize to be located in an areawhich does not need to be sterilized as regularly.

[0030] This element for injecting or coupling-in the illuminating lightis preferably designed such that the processing or treatment beam canalso be injected via the same optical element, so that this element isalso an optical multifunction element for the purposes of thisinvention.

[0031] What has been stated above applies to an even greater extent tothe arrangement of the laser light source in the laser treatmentappliance, since the laser light source generally comprises complex andhence sensitive apparatuses, so that these are preferably arranged in“rear” components, that is to say at a distance from the treatment end.

[0032] However, in another embodiment, it is also possible for thecomponent itself to have the illuminating light source and/or the laserlight source. This may be the case especially in apparatuses where, forexample, a simple diode laser can be used as the laser light source.However, it is also possible for such a component to be a componentwhich is a relatively long way away from the treatment end of the lasertreatment appliance, so that there are no problems in providing theilluminating light source and/or the laser light source in thiscomponent.

[0033] The advantages of the present invention are in particular highlyimportant when the component is a handpiece, that is to say thetreatment end piece of a laser treatment appliance, since both thetreatment laser beam and the illuminating light must be available, inthis area, in all cases. A handpiece such as this is designed such thatespecially the treatment end optical elements are in the form of opticalmultifunction elements. These optical multifunction elements are usedespecially in this end area shortly in front of the area to be treated,which also leads to highly effective illumination in the same direction.In this context, “illumination in the same direction” should beunderstood as meaning that both the treatment laser beam and the visiblelight for illumination are transmitted to the area to be treatedessentially from the same direction and at least partially overlapping,thus very largely, or even completely, avoiding shadowing.

[0034] The invention preferably provides for at least the last of thefirst optical elements in the direction of the course of the treatmentlaser beam to be in the form of a multifunction element. This lastoptical element is generally the outlet window as described above.

[0035] In a further particularly preferred embodiment, at least the lastof the first optical elements, which still influences the course of thetreatment laser beam, is in the form of an optical multifunctionelement. This ensures that this last optical element which steers orinfluences the treatment laser beam, for example a mirror or a lens, isat the same time also used for illumination, thus ensuring the effect,as described, above of emission in the same direction and effectiveillumination without shadowing.

[0036] The invention also relates to a laser treatment appliance havingan illumination system for use in the field of medicine, having a laserlight source and an illuminating light source, with the illuminationsystem and at least one optical element for the treatment laser beambeing in the form of an optical multifunction element, such that thevisible, preferably white light for illumination, is also steered viathis at least one optical multifunction element.

[0037] The advantages of such a laser treatment appliance with anillumination system correspond to those which have been explained inconjunction with the component according to the invention, with thelaser treatment appliance preferably having a component as has beendescribed above.

[0038] A “white light-emitting diode” may also be provided as anilluminating light source, which combines light at different wavelengths(in particular a combination of a red, a green and a blue LED), so thatthe desired uniform white illumination is ensured. A “whitelight-emitting diode” such as this avoids the speckles described abovewhich occur with monochromatic laser light, for example with the pilotbeams explained above. Furthermore, standard illuminating light sources,for example incandescent lamps or glow lamps, may be used.

DESCRIPTION OF THE DRAWING

[0039] These and further characteristics and advantages of the presentinvention will be explained in more detail with reference to theschematic drawings below, in which:

[0040]FIG. 1 shows a first embodiment of a laser treatment applianceaccording to the invention;

[0041]FIG. 2 shows a second embodiment of a laser treatment applianceaccording to the invention;

[0042]FIG. 3 shows a third embodiment of a laser treatment applianceaccording to the invention.

DESCRIPTION OF THE PREFFERED EMBODIMENTS

[0043]FIG. 1 shows, schematically, a first embodiment of a lasertreatment appliance 5 according to the invention, with a component 20and a component 30 of the laser treatment appliance 10. The component 20is the handpiece, which does not specify the boundaries of the component30 in more detail, may be fitted directly to the handpiece 20 or elsemay also be at a distance from it, in which case further components,which are not shown in FIG. 1, may be provided between the components 20and 30.

[0044] At this point, it should be noted that FIG. 1 illustrates thecomponents 20 and 30 only schematically, and that all the components20,30 and possibly further components are connected to one another inone operating state.

[0045] The laser light source 119 emits a treatment laser beam 112,which is guided via a system of first optical elements by the component30 and the handpiece 20 to an area 50 that is to be treated. In theprocess, the treatment laser beam 112 passes through a focussing lens142, is reflected by a chromatic mirror element 144 at an angle of about90°, then passes through a lens 146, and is then aimed by two furthermirrors 148 and 150 in the direction of the handpiece 20. The mirrors148 and 150 can move and form a scanning apparatus, so that theprocessing laser beam can be steered such that it scans a predeterminedpattern in a predetermined time on the surface to be treated. Inprinciple, it is also possible to provide a mirror mounted in a fixedposition and only one mirror moving about two axes instead of the twomoving mirrors 148 and 150, which can each be pivoted about one axis,and with these pivoting axes being arranged essentially at right anglesto one another.

[0046] The treatment laser beam 112 reflected by the mirror 150 isguided via a lens 152, which is itself part of the handpiece 20 in aninterior 24 of the handpiece 20, in which the treatment laser beam 112is guided freely. In principle, it is also possible for the lens 152 notto be part of the handpiece 20 but to be part of a coupling or of anelement which is arranged in front of the handpiece.

[0047] Since the handpiece 20 is designed to be curved in the directionof its treatment end in order to achieve better ergonomic handling, twofurther mirrors 154 and 156 are provided in the interior 24 of thehandpiece 20, steering the treatment laser beam 112 onto a mirror 158which is located in the head part 22 of the component 20. The mirror 158is the last light-steering optical element, which steers the treatmentlaser beam 112 through a light outlet window 172 onto the area 50 to betreated.

[0048] The light outlet window 172 is also an optical element for thepurposes of the invention, but with this optical element essentiallyhaving no influence on the profile of the treatment laser beam 112.

[0049] The embodiment of the laser treatment appliance 10, asillustrated in FIG. 1, furthermore has an illuminating light source 120,which, in this embodiment, is formed by a white light-emitting diode.

[0050] The first optical elements 152, 154, 156, 158 and 172 asexplained above are thus in the form of optical multifunction elementswhich, in addition to the treatment 20 laser beam 112, also pass on thevisible light 122 for illumination.

[0051] At this point, it should be noted that the treatment laser beam112 and the visible light 122 do not influence one another, since theyare at different wavelengths. The optical multifunction elements 152,154, 156, 158 and 172 are in this case designed such that they have acomparable influence both on the light at the wavelength of thetreatment laser beam 112 and on the light at the wavelength of thevisible light 220, that is to say the mirrors 154, 156,158 arereflective for both wavelengths or wavelength bands, while the lens 152and the light outlet window 172 are designed to be transmissive for bothwavelengths.

[0052] Widely differing lasers may be used as the laser light source110, even pulsed lasers, which preferably emit light at a wavelengthbetween 900 nm and 1100 nm, and preferably 1030 nm or 1064 nm. However,the laser light source 110 is in no way restricted either to a specificwavelength or to a specific laser system.

[0053] The desired laser system and the desired wavelength of thetreatment laser beam, which is emitted by the laser light source 110,are critically dependent on the desired purpose of use. It should alsobe noted at this point that the expression laser light source 110, whichis illustrated only schematically in FIG. 1, should also be understoodas referring to a complex system with a number of lasers, for exampleincluding pump lasers. The laser light source 110 may also havefrequency converters or different further optical elements.

[0054] The illuminated light source 120 (in this case a standardincandescent lamp) is arranged (seen in the emission direction) parallelto the treatment laser beam 112, with the visible light 122 passingthrough a lens 174 and a further lens 176 for illumination from theilluminating light source 120, and then be injected by two mirrors 162and 164 into the lens 152 of the handpiece 20. The lenses 174 and 176 inthis embodiment of the illuminating light provide the appropriatedivergence and thus control the desired diameter in order to illuminatethe working area as desired.

[0055] The lens 152 is thus the first optical multifunction element,which is used both for steering and for influencing the treatment laserbeam 112 as well as for steering the visible light 122.

[0056] The mirrors 162, 164, 154, 156 and 158 are in this case designedsuch that, although the visible light 122 is injected essentiallyparallel to the treatment laser beam 112 via the lens 152 into thehandpiece 20, the treatment laser beam 112 and the visible light 122 aresteered in the same direction by the mirror 158 onto the area 50 to betreated.

[0057] The treatment laser beam 112 is very highly focussed, while thevisible light 122 illuminates an illuminated area 52, which isessentially circular, with the centerpoint of the circle essentiallybeing coincident with the area 50 to be treated. The size of theilluminated area 52 may be chosen as required, depending on theapplication, and in the field of dentistry this area 52 will have adiameter of about 5-10 mm, and preferably 6 mm.

[0058] The embodiment of the laser treatment appliance 10 as illustratedin FIG. 1 has the advantage that, in addition to processing andtreatment, it can also be used for diagnosis or analysis of the area tobe treated, or for analysis during treatment.

[0059] Especially in the field of dentistry, it is possible tospectroscopically investigate the plasma which is produced during theremoval of tooth material, without having to provide an additional laserlight source.

[0060] In the embodiment shown here, the radiation 130, which isproduced by the plasma, and is also referred to as spectroscopy light,is passed to the mirror 144 from the area to be treated in the rearwarddirection via the optical elements 172, 158, 156, 154, 152, 150, 148,146. The mirror 144 is in this case designed such that it is essentiallytranslucent for the broadband spectrum of the spectroscopy light, sothat the radiation 130 and the spectroscopy light are passed through themirror 144 to a lens 160, which focusses the radiation 130 or thespectroscopy light and feeds it via an optical fiber 132 to an opticalevaluation unit, in this case to a spectrometer 134.

[0061] The spectroscopy light or the radiation 130 is evaluated in thespectrometer 134, and evaluation units, for example computers ,or thelike which may, of course, be connected to the spectrometer for thispurpose.

[0062] With regard to a handpiece which allows such spectroscopy,reference is made to the parallel application (official file reference101 15 426.7), whose entire contents are included in this application,by reference.

[0063] A further advantage of the embodiment illustrated in FIG. 1 isthat the illuminating light is not passed via the mirrors 148, 150,which are in the form of a scanner, so that the illuminating light isnot influenced by them. This therefore avoids any possible flickering ofthe illuminating light. The same is true for the embodiments shown inFIGS. 2 and 3.

[0064]FIG. 2 shows a further embodiment of a laser treatment appliance10 according to the invention. The same or similar elements are providedwith identical reference symbols.

[0065] The treatment laser beam 112 emitted from the laser light source110 passes through the laser treatment in an analogous manner to thatwhich has been described in conjunction with FIG. 1.

[0066] In contrast to the embodiments shown in FIG. 1, in the embodimentof the laser treatment appliance 10, as shown in FIG. 2, theilluminating light source 120 is arranged in the handpiece 20 itself,with the emitted visible light 122 passing through a lens 166 beforebeing passed to the mirror 158, which reflects the visible light 122such that it illuminates the area 52. In this embodiment, only themirror 158, that is to say the last light-steering or light-influencingoptical element, and the light outlet window 172 are in the form ofoptical multifunction elements, which pass on both the treatment laserbeam 112 and the visible light 120 for illumination. In thisparticularly advantageous embodiment, only the last elements 158, 172 atthe treatment end are thus in the form of optical multifunctionelements. Owing to the arrangement of the illuminating light source 120in the area of the treatment end of the handpiece 20, virtually noadditional optical elements are required exclusively for the visiblelight 122 in this embodiment. The only second optical element which isprovided exclusively for the visible light 122 is the lens 166.

[0067] The spectroscopy which has been explained in conjunction withFIG. 1 is also possible with this embodiment, and in this contextreference is made to the description relating to FIG. 1, in order toavoid repetitions.

[0068] Yet another embodiment of the laser treatment appliance 10according to the invention is illustrated in FIG. 3, with thisembodiment being the most similar to the embodiment shown in FIG. 2.

[0069] In the embodiment shown in FIG. 3, the illuminating light source120 (in this case once again an incandescent bulb) is also accommodatedin the handpiece 20, with the visible light 122 for illumination notbeing guided freely, at least initially, but being steered via anoptical fiber 168 into the vicinity of the head part 22.

[0070] In this embodiment, the optical fiber 168 consists of a fiberpack, which ends shortly in front of the head part 22 in an essentiallyannular fiber bundle end 170, in whose interior the treatment laser beam112 runs. In principle, of course, it is also possible to provide acircular fiber bundle, with essentially the entire area of the circlebeing filled with fiber ends. In this case, this circular fiber bundleends parallel to the treatment laser beam.

[0071] The visible light 122 for illumination is steered or directedfrom the fiber bundle end 170 via the mirror 158, which is in the formof an optical multifunction element, to the area 52 to be illuminated,passing through the outlet window 172.

[0072] In this embodiment as well, at least the mirror 158 and the lightoutlet window 172 are in the form of optical multifunction elements, sothat this results, in particular, in illumination which is in the samedirection as that in which the treatment laser beam 112 runs, henceensuring shadow-free illumination of the area 50 to be treated.Furthermore, the sensitive optical fiber 168 and the sensitive fiberbundle end 170 are arranged entirely in the interior 24 of the handpiece20, so that they are protected against external influences, and henceagainst damage.

[0073] Those skilled in the art will be able to implement furtherpossible embodiments, in particular combinations of the embodimentsillustrated in FIGS. 1 to 3, without having to depart from the subjectmatter of the invention. Depending on the field of application, thoseskilled in the art will be able to design the laser treatment applianceand the individual components in accordance with the requirements.

[0074] The embodiment illustrated in FIG. 1 has the advantage that thehandpiece component t does not contain any live parts and, does notcontain any excessively sensitive or expensive optical components, sothat this firstly ensures high reliability during operation and,secondly, the handpiece 20 is not subject to excessive loads during thesterilization processes which are frequently required when used in thefield of medicine.

[0075] The embodiment shown in FIG. 3 has, in particular, the advantagethat a number of light sources can also be arranged in an annular shapearound the axis of the treatment laser beam 112, in which case the lightfrom the number of light sources can be carried in individual opticalwaveguides or in individual optical fibers in the optical waveguide 168.An annular arrangement of a number of illuminating elements such as thiscan in principle also be used in all the other described embodiments.

[0076] A straight handpiece may, of course, also be used instead of theergonomic, curved embodiment of the handpiece as shown in all thefigures. In particular, it is also possible to emit the treatment laserbeam as well as the visible light for illumination in the axis directionof the element at the treatment end, that is to say not, as described inthe embodiments, at an angle of 90°, although a configuration such asthis is particularly advantageous for dentistry treatment. Other angulararrangements are, of course, also feasible, varying depending on thefield of use and application.

[0077] Finally, it should also be mentioned that, in principle, it isalso possible to equip the laser treatment appliance with a pilot laserin addition which, as explained above, can be used as an “aimingapparatus”. In principle, it is also possible to provide a furthermonochromatic light source (diagnosis laser beam) in the laser treatmentappliance if, for example, it is desirable to use fluorescence toanalyze the material to be treated. The monochromatic light forproducing the fluorescence may likewise, if desired, be passed andsteered via the optical elements and via the multifunction elementsaccording to this invention. A combination of a laser as a pilot laserand as a diagnosis laser is also feasible, since fluorescence can alsobe stimulated by a laser beam which emits in the visible wavelengthband.

[0078] The features which have been disclosed in the presentdescription, the claims and the drawings may be important to theimplementation of the invention, in its various embodiments, bothindividually and in any given combination.

1. A laser treatment appliance having an illumination system, inparticular for use in the field of medicine, which has a laser lightsource (110) for producing a treatment laser beam (112) which is guidedessentially freely, as well as an illuminating light source (120) forproducing a visible light (122) for illuminating an area (50) to betreated, and one or more first optical elements (142, 144, 146, 148,150, 152, 154, 156, 158, 172) via which the treatment laser beam (112)is passed on, with at least one of the first optical elements (142, 144,146, 148, 150, 152, 154, 156, 158, 172) being in the form of an opticalmultifunction element (152, 154, 156, 158, 172), and such that thevisible light (122) for illumination is also directed at least over thisat least one optical multifunction element (152, 154, 156, 158, 172)characterized in that the laser treatment appliance furthermore has anoptical evaluation apparatus (134) for diagnosis or analysis ofradiation (130) which is produced during the treatment process, and allthe optical multifunction elements (152, 154, 156, 158, 172) aredesigned such that they influence the treatment laser beam (112) and thevisible illuminating light (122) essentially in an equivalent reflectingand/or transmitting manner, and the laser treatment appliancefurthermore has a beam splitter (144), which extends at least over theentire cross section of the treatment laser beam (112), for outputtingthe radiation (130), and which is arranged between the laser lightsource and the first multifunction element (152; 158) in the incidencedirection of the treatment laser beam (112) such that the visible light(122) from the illuminating light source (130) does not pass through it.2. The laser treatment appliance as claimed in claim 1, characterized inthat said appliance is designed such that the treatment laser beam (112)is guided essentially freely in it.
 3. The laser treatment appliance asclaimed in claim 1 or 2, characterized in that said appliance has afirst optical element which is essentially in the form of a light outletwindow (172) which transmits the laser treatment light and does notsignificantly influence the profile of the treatment laser beam (112).4. The laser treatment appliance as claimed in claim 3, characterized inthat at least the light outlet window (172) is in the form of an opticalmultifunction element.
 5. The laser treatment appliance as claimed inone of the preceding claims, characterized in that said appliance has atleast one first optical element (152, 154, 156, 158), which influencesthe profile of the treatment laser beam (112).
 6. The laser treatmentappliance as claimed in claim 6, characterized in that at least one ofthe first optical elements (152, 154, 156, 158) which influence thetreatment laser beam is in the form of an optical multifunction element(152, 154, 156, 158).
 7. The laser treatment appliance as claimed inclaim 5 or 6, characterized in that at least one of the first opticalelements which influence the treatment laser beam is a mirror element(154, 156, 158).
 8. The laser treatment appliance as claimed in claim 5to 7, characterized in that at least one of the first optical elementswhich influence the treatment laser beam is a focussing lens (152). 9.The laser treatment appliance as claimed in one of the preceding claims,characterized in that all the first optical elements are in the form ofoptical multifunction elements.
 10. The laser treatment appliance asclaimed in one of the preceding claims, characterized in that saidappliance has a component (20) which has at least one optical element(152) for injecting the illuminating light (122) into the component(20).
 11. The laser treatment appliance as claimed in claim 10,characterized in that the optical element (152) is designed forinjecting the illuminating light (122) into the component such that thetreatment laser beam (112) can also be injected via this element (152)into the component (20).
 12. The laser treatment appliance as claimed inone of the preceding claims, characterized in that said appliance has acomponent which itself comprises the illuminating light source (120)and/or the laser light source.
 13. The laser treatment appliance asclaimed in one of claims 10 to 12, characterized in that the componentis a handpiece (20) at the treatment end.
 14. The laser treatmentappliance as claimed in claim 13, characterized in that the handpiece(20) is designed such that the visible light (122) for illuminationemerges from the handpiece (20) essentially in the same direction as thetreatment laser beam (112).
 15. The laser treatment appliance as claimedin one of the preceding claims, characterized in that said appliance isdesigned such that the beam axis of the treatment laser beam (112) onthe one hand and the beam axis of the visible light (122) forillumination on the other hand are offset with respect to one another,at least in the first optical multifunction element (152; 158) in theemission direction.
 16. The laser treatment appliance as claimed in oneof the preceding claims, characterized in that a white light-emittingdiode or an incandescent lamp is provided as the illuminating lightsource (120).
 17. The laser treatment appliance as claimed in one of thepreceding claims, characterized in that said appliance furthermore has afurther laser light source as a stimulation light source forfluorescence of the material to be treated.